在此页

• 句法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

DataView() constructor is used to create DataView 对象。

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

句法

new DataView(buffer [, byteOffset [, byteLength]])
					

参数

buffer

An existing ArrayBuffer or SharedArrayBuffer to use as the storage backing the new DataView 对象。

byteOffset 可选

The offset, in bytes, to the first byte in the above buffer for the new view to reference. If unspecified, the buffer view starts with the first byte.

byteLength 可选

The number of elements in the byte array. If unspecified, the view's length will match the buffer's length.

返回值

A new DataView object representing the specified data buffer. (That probably wasn't a very helpful description.)

You can think of the returned object as an "interpreter" of the array buffer of bytes — it knows how to convert numbers to fit within the buffer correctly, both when reading and writing to it. This means handling integer and float conversion, endianness, and other details of representing numbers in binary form.

异常

RangeError

Thrown if the byteOffset or byteLength parameter values result in the view extending past the end of the buffer.

For example, if the buffer is 16 bytes long, the byteOffset is 8, and the byteLength is 10, this error is thrown because the resulting view tries to extend 2 bytes past the total length of the buffer.

范例

Using DataView

var buffer = new ArrayBuffer(16);
var view = new DataView(buffer, 0);
view.setInt16(1, 42);
view.getInt16(1); // 42
					

规范

规范
ECMAScript (ECMA-262) The definition of 'DataView constructor' in that specification.

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
DataView() 构造函数	Chrome 9	Edge 12	Firefox 15	IE 10	Opera 12.1	Safari 5.1	WebView Android 4	Chrome Android 18	Firefox Android 15	Opera Android 12.1	Safari iOS 4.2	Samsung Internet Android 1.0	nodejs 0.10
DataView() without new throws	Chrome 11	Edge 13	Firefox 40	IE No	Opera 15	Safari 5.1	WebView Android ≤37	Chrome Android 18	Firefox Android 40	Opera Android 14	Safari iOS 5.1	Samsung Internet Android 1.0	nodejs 0.10
SharedArrayBuffer accepted as buffer	Chrome 68 68 不支持 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This was a temporary removal while mitigations were put in place.	Edge 79	Firefox 79 79 57 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Disabled From version 57: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 55 — 57 不支持 46 — 55 Disabled Disabled ). To change preferences in Firefox, visit	IE No	Opera No	Safari 10.1 — 11	WebView Android 60 — 63 不支持 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place.	Chrome Android 60 — 63 不支持 60 — 63 Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place.	Firefox Android 57 Disabled 57 Disabled Support was disabled by default to mitigate speculative execution side-channel attacks (Mozilla Security Blog) . Disabled From version 57: this feature is behind the javascript.options.shared_memory preference (needs to be set to true ). To change preferences in Firefox, visit about:config. 不支持 55 — 57 不支持 46 — 55 Disabled Disabled ). To change preferences in Firefox, visit	Opera Android No	Safari iOS 10.3 — 11	Samsung Internet Android No 不支持 No Chrome disabled SharedArrayBuffer on January 5, 2018 to help reduce the efficacy of speculative side-channel attacks . This is intended as a temporary measure until other mitigations are in place.	nodejs 8.10.0

图例

完整支持

完整支持

不支持

不支持

见实现注意事项。

用户必须明确启用此特征。

用户必须明确启用此特征。

另请参阅

• DataView

元数据

• 最后修改： May 19, 2020

相关话题

1. 标准内置对象
2. DataView
3. 特性
   1. DataView.prototype.buffer
   2. DataView.prototype.byteLength
   3. DataView.prototype.byteOffset
4. 方法
   1. DataView.prototype.getBigInt64()
   2. DataView.prototype.getBigUint64()
   3. DataView.prototype.getFloat32()
   4. DataView.prototype.getFloat64()
   5. DataView.prototype.getInt16()
   6. DataView.prototype.getInt32()
   7. DataView.prototype.getInt8()
   8. DataView.prototype.getUint16()
   9. DataView.prototype.getUint32()
   10. DataView.prototype.getUint8()
   11. DataView.prototype.setBigInt64()
   12. DataView.prototype.setBigUint64()
   13. DataView.prototype.setFloat32()
   14. DataView.prototype.setFloat64()
   15. DataView.prototype.setInt16()
   16. DataView.prototype.setInt32()
   17. DataView.prototype.setInt8()
   18. DataView.prototype.setUint16()
   19. DataView.prototype.setUint32()
   20. DataView.prototype.setUint8()
5. 继承：
6. Function
7. 特性
   1. Function.arguments
   2. Function.caller
   3. Function.displayName
   4. Function.length
   5. Function.name
8. 方法
   1. Function.prototype.apply()
   2. Function.prototype.bind()
   3. Function.prototype.call()
   4. Function.prototype.toSource()
   5. Function.prototype.toString()
9. Object
10. 特性
    1. Object.prototype.__proto__
    2. Object.prototype.constructor
11. 方法
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.valueOf()
    12. Object.setPrototypeOf()